Light is an important parameter in the health of an aquarium. As we are recreating an ecosystem in a closed container, we must understand how it all begins. Light is the impetus for life in virtually all environments we know. The sun produces the light that starts life, and begins the chain that includes almost every life form on earth. Plants (that utilize sunlight through photosynthesis) and animals form the beginnings of the food chain. Managing balances within the ecosystem, including the role of light, can help us provide optimum conditions for the animals and plants in our aquarium. Let us help you pick the pefect lighting syestem for your aquarium. We have in stock a wide variety of fixtures and replacement bulbs. Stop in to see our many opitons on display, today!
Types of Lighting
This type of bulb has a screw-in base, much like an ordinary lamp bulb. Wattages generally range from 5 watts to 25 watts. This bulb’s main benefit is expense, in that the fixtures and bulbs are relatively inexpensive. However, it is inefficient in power consumption and has poor color reflection off the fish, plants and decorations in the tank. Additionally this type of bulb releases a lot of heat to the water and can result in fluctuating temperatures in the aquarium.
This bulb is by far the most common source of lighting used on aquariums. It has many advantages, such as being energy efficient, cool running, available in a wide variety of sizes and spectrums it is also relatively inexpensive for both the bulbs and fixtures. Fluorescent bulbs come in different thickness and the measurement for this is the T factor. Most bulbs will be listed as T-5, T-8, T-10, or T-12.
High Output Fluorescent
These fixtures require special ballasts and bulbs to operate. They can be convenient to use because they behave in the same manner as standard fluorescent bulbs, just with more light output or intensity. The main difference is the increased wattage. These fixtures run at 2-3 times the wattage of standard fluorescents. The fixtures produce powerful and intense light, and can be a boon to reef keepers. The High Output (H.O.) fixtures also run fairly hot, and may require additional cooling.
Power Compact Fluorescent
Power compact fluorescents, or power compacts, are another addition to the world of aquarium lighting. They differ from other fluorescent in many regards, not the least of which is that they consist of single ended bulbs, instead of double ended. They run in a U-shape configuration, with a set of contact pins at the base. Power compacts require a special ballast and fixture to operate. These bulbs have high intensity, low running temperatures, long replacement schedules, and ease of use. The bulbs themselves are still fluorescent, but are very bright yet run cool, and use little energy to operate, thanks to electronic ballasts and better engineering. The intensity of the bulbs is between standard fluorescent and High Output fluorescent lighting, suitable for reef keeping and planted aquariums.
Metal halide fixtures and bulbs are generally considered the highest level intensity available for the home aquarium. Much like the previous examples, there are special bulbs and fixtures required for operation. There are two main styles of bulbs (and therefore fixtures). There are single ended bulbs, some screw (mogul base) and others have a pin configuration (HID). Double ended bulbs (dubbed “HQI”) remind one of fluorescent bulbs, only there are no pins, simply contacts on either end of the bulb. Metal halide bulbs are so named because they contain both metals and halides in a small envelope of quartz that produces the light. This envelope is placed inside a larger quartz or glass bulb that is the shape of the bulb we see. The reaction occurring is similar to a fluorescent bulb, with a current moving through gases inside the small envelope. The mixture of gases and compounds are what create the many different styles of bulbs.This type of light produces an extremely bright light, and is considered the top end of high intensity lighting. Very few photosynthetic animals and plants require more light than a metal halide bulb can provide. Additionally, metal halides produce what is known as “point source” style of lighting. This means that the light is produced from a single point, as opposed as from a broad area, as in fluorescent bulbs. This replicates the effect that the sun gives us with realistic shadows and lighting. Over water, a pleasing ripple effect is visible on everything submerged, so adding to the popularity of the bulb.Metal Halide bulbs, ballasts and fixtures need to be constructed of strong materials built to withstand the rigors of the lighting itself. The bulbs generally range in wattage from 175 watts to well over 1000 watts. For such a large draw, overbuilt ballasts are required to operate. Additionally, metal halides produce an enormous amount of heat. The temperatures in the bulb approach 2000°F, and involve pressures of 3 to 4 atmospheres. This results in the fixtures being made of materials able to withstand high heat. The high level of heat liberated from these bulbs can transfer to the water, making it necessary to cool the water with additional equipment. Since the bulbs utilize a reaction that results in high heat and pressures, the quartz surrounding the reaction tends to break down over time, becoming opaque and changing the spectrum produced by the bulb and lowering overall output. This phenomenon means that the bulbs themselves should be changed out at least once a year.
Over the past few years LED (light emitting diodes) lighting has made huge in-roads for the consumer in every day uses, from Christmas tree lighting to indoor and outdoor home lighting to aquariums. What was a very expensive option has come down in price due to advances in technology and many manufacturers wanting to “get in the game”. LED lighting offers some very unique advantages over other types of lighting, particularly in energy use----they use about ½ of the energy of others. They run “cool” to the touch, unlike halide, incandescent or H.O. fluorescent bulbs and so the need for extra expense of chilling equipment to maintain constant water temperature is not required. They provide a “shimmering” effect to aquarium water that is desired but not found with other standard aquarium lighting. Lastly, but not at least the bulbs themselves last a very long time, averaging 10 years (under normal use) before replacement as opposed to yearly for all other types of bulbs. So even though the upfront costs make them much more expensive than other types of lighting, over time they work out to be much more economical and worth the investment. They are available in many “colors” to match aquarium types (freshwater, planted, marine, reef, etc.) and wattages. It is suggested that about 2 – 4 watts per gallon should serve well.
Plasma and LCD
Just follow the TV trend and you’ll be current on other types of lighting being developed for aquarium use. These are very new and just now being introduced and tested so there really is no history on these types of lighting. Theoretically they should be usable alternatives although very pricey at present. Updates to follow after R&D is complete.
Bulb Spectra Types
Lighting known as “daylight” will appear very much like normal daylight. Usually the color temperature will be around 5 – 6,500°K, and the light spectrum chart will show output across many areas of wavelengths.
Actinic lighting is that which appears to be blue in our view. Color temperatures for these bulbs generally range from 7 – 14,000°K. A light spectrum chart will show strengths in the shorter wavelengths of the visible spectrum, around 400-450 nanometers.
This label denotes the combination of a daylight spectrum with an actinic spectrum in one bulb. This type of bulb is designed for users that have room for only one bulb in the fixture, be it fluorescent, power compact, or other.
These bulbs have a spectrum the focuses on the spectra of light that plants are able to use. When looking at the spectrum of visible light, we see that the color shifts (from shorter to longer wavelengths) from purple to blue to green to yellow to orange and finally to red. Since plants reflect the green wavelengths (they look green to us), the spectra useful for most plants consists of red and blue wavelengths. Most of the bulbs designed for this will appear yellowish to reddish. There is some minor benefit to plants with these bulbs, but with the lack of green spectra, most plants don’t look very green under these lights. Furthermore, higher intensity is a better way to enhance the growth and colors of plants.
Bulbs suited for reefs tend to emulate the lighting conditions found on reefs in the wild. Since water is an efficient filter of longer wavelengths, blue is a predominant color under water. Reef bulbs are generally touted with color temperature numbers and spectrum graphs—both of which have been previously discussed. Just remember that intensity is the primary focus; what the bulb looks like (i.e. the spectrum) is more aesthetic than anything.
See our Aquarium Lighting Fish Tips for more detailed information.